Chair.



ANo. 723,465. PATBNTED 11m44.190s.

A.' N. HGRNUNG, JR.

GHAIR.-

APPLIOAVTION FILED 00T. 14, 1901.

N0 MODEL.

WWIIII'IIHHI l lllllllllllllflllllil UNITED STATES PATENT OEETCE.

ANTON Nl HORNUNG, JR., OF CHICAGO, ILLINOIS, ASSIGNOR TO LOUIS HANSON, OF CHICAGO, ILLINOIS.

CHAIR.

SPECIFICATION forming part of LettersfPatent No.' 728,465, dated March 24, 1903.

Application filed October 14,1901. Serial No. 78,526. (No model.)

To @ZZ whom, it may concern.

Be itknown that LANTON N'. HORNUNG, Jr., a citizen of the United States, residingat Chicago, in the county of Cook aud State of Illinois, have invented certain new and useful Improvements in Chairs, of which the following is a specication, reference being had to the accompanying drawings,forming a part thereof. l

The purpose of this invention is to provide an improved chairof a general class suitable for dentists or barbers chairs or surgeons operating-chairs, in which adjustments of the seat about a vertical axis and of a leg or foot rest and back in respect to the seat are to be made and in which perfect fixedness ofposition of the several parts as adjusted is essential.

It consists in the features of construction set out in the claims and which are fully described and shown herein by reference to the drawings, in which- Figure lis a partly-sectional side elevation of myimproved chair,se'ction being made fore and aft through the chair frame, back, and leg-rest. Fig. 2 is a detail section at the line 2 2 on Fig. vl. Fig. 3 is adetail side elevation, partly sectional, at the plane denoted by the line 3 3 on Fig. 2, but on an enlarged: Fig. 4 is a section at the line 4 4 on.- Fig. 5 is a detail section at the line scale. Fig. 3. 5 5 on Fig. 3.

In the drawings I have shown the features of my invention as applied to a chair which is provided with hydraulic means for raising and lowering it, these means being contained in the hydraulic base A and not specifically illustrated and not to be herein described, since they are shown in and covered by my application, Serial No. 54,833, led April 8,

1901, and now pending in the Patent Office. Y

My present invention is concerned with the portion of the chair above said hydraulic base, and this. portion will now be described.

B is a base, having a stem B, which extends into the hydraulic base when such base is employed.-

C is a standard, vertically pivoted by its stem C in the base B and having the chairbottomD mounted on its upperl side.`

E is the back, which is pivoted at e to the chair-bottom D.

F is the footor leg rest, hinged to the chairbottom D at the side opposite t-he'back.

There are two links H, of which one is shown so formed as to serve as side arms for the chair, said linksextending, respectively, from the opposite sides of the foot or leg rest to the corresponding sides of the back E, to which they are connected at points above the hinge of the back to the chair-bottom, their connection with the lfoot or leg rest being above the hinge-line of said rest and thesaid hinge-lines of the back and foot-rest and the points of connection of the said arms or links to said parts, respectively, being such that the tilting or swinging of the foot-rest from lower to higher position for bringing the limbs of the user up toward horizontal position inclines the back rearward.

The base B has formed rigid and preferably integral with it a circular horizontal rack B2, and a dog G is provided adapted to engage said rack, said dog being mounted and adapted to slide vertically between lugs C2 C2, which project from the standard C, the dog having further guidance by means of its stem G',whose upperend projects through the horizontal iiauge c, which constitutes the means by which the standard is secured tothe chairbottom. The dogisheld normally downward by gravi-ty and further kept in engagement with the rack B2 by means Of a spring J,which is coiled around said stern G of the dog, being stopped between the shoulder g' of latter vand the iiange c of the standard.

In order to prevent any play or lost motion Abetween the dog and therack, which would permit the chair to oscillare about its vertical axis notwithstanding the engagement of the dog with the rack, four features of construction are adopted, each of which singly tends to this result, but all of which coperate thereto. First, the teeth b2 of the rack are beveled or tapered, so that4 the dog, having teeth adapted to mesh with those of the rack,

shall by its engagement, with such teeth be wedged thereon to more or less, taking up any lateral play which might otherwise exist; second, the teeth of the dog are beveled or IOO Azo

tapered, so that entering between any two consecutive teeth of the'rack they tend to take up the lost motion and effect an engagement without play; third, the rack is inclined dog or of the t-eeth of the rack; fourth, the dog is tapered in horizontal cross-section, widening from the inner or back side toward the outer side at which the teeth are formed on the lower end to engage the rack, and the lugs` C2 C2, between which the dog is guided, have their proximate faces beveled to correspond with the Lapel-of the dog in horizontal cross-section, so that the dog tends to seat without play in the space between the lugs, the feature of construction or action which operates to guide or force the dog inward toward the axis of the chair having the effect to take up or prevent such play and render the dog fixed as respect to lateral motion with respect to the standard. The inclination of the rack above described has the eect to guide the dog inward when it is forced downward by its spring or by gravity, and thus cooperates wih the horizontal taper of the dog and its guide-bearing to produce engagement without play between the dog and the standard at one side and between the ldog and the rack at the other side, thus making the rack' rigid with the standard without play when it is locked thereto by the dog. The inclination of the rack and the wedging of the teeth of the dog in engagement therewith by virtue of such inclination has another functionnamely, that whereas if the rack were hori-lA zontal with beveled or V-shaped teeth for engagement with similar teeth of 'the dog said dog might be forced out of engagement by forcibly swinging the chair around its axis, the bevel of t-he engaged teeth of rack and dog facilitating their disengagement-under such action. The inclination of the rack and the engagement with wedging eect which is rendered possible by the taper of the spaces between. the teeth which lsuch inclination causes adapts the rack to resist any tendency of the dog to become disengaged therefrom when force is applied tending to rotate the chair.

For the purpose of operating the dog to lift it out of engagement with the latter I provide a lever K, fulcrumed on a stud C4, projecting horizontally from a boss C40 on the standard C. The lever has an aperture K', and the dog has the cross-bar G2 at the lower end of the stem, the under face ofy said bar constitutingashoulderforstoppingthespring J, the cross-bar being adapted to pass through the aperture K',and the dog then being turned onequarter way around said crossbar overhangs' the sides of the aperture, so that the lever may engage the cross-bar to lift the dog. A rock-shaft L is journaled inhangers M M, projecting downward from the chair-bottom, and is provided Vwith a handle or lever-arm L2, extending up alongside the chair within reach of the user, by which the shaft may be rocked. The rock-shaft has also a lever arm or finger L', which operates asthe shaft is rocked in one direction to lift the lever K by engaging under said lever atits outer end, thereby causing the lever to lift the dog out of engagement with the rack. A small notch k in the under face of the lever at a position vertically above the rock-shaft when the lever is upholding the dog forms a seat for the end of the finger L', in which it becomes lodged and engaged when said finger is erect from the rock-shaft, thus rendering the parts comparatively difiicult to disturb from this position, so that the dog may be held ont of engagement without continuous attention of the user when the chair is to be left free to rotate or even during the short time during which it is being swung from one position to another.

N is a rack-bar hinged at N' to the rear under side of the foot or leg rest F and extending rearward from itshinge under the chairbottom alongside the stem of the standard C, said stem of standard having a ledge or lug IC-L C4, on which the rack-bar rests and may slide back and forward.

Q is a dog fulcrumed upon a stud C5, which ju'ts horizontally from the boss C49 in the opposite direction from the stud C4. The dog Q is provided at its forward end and lower side with teeth qq, adapted to engage the teeth of the rack-bar N, the pivot of the dog being somewhat above the level of the rack, so that the dog trends downward from its pivot to its engagement with the rack. The teeth of the rack are inclined forward, so that they stand substantially at right angles to the trend of the dog when it is engaged therewith, and the teeth of the dog are correspondingly inclined to effect good engagement, the intention and result being to cause the dog to lock the rack positively against disengagement by mere movement of the rack either back or forward.

R is a spring which is coiled around the hub of the dog or around the boss from which the stud pivot projects, having one end stopped against the under side of the liange c of the standard and the otherend hooked, so as to engage above the dog, thus operating to hold the latter downward at its toothed end Vintoengagement with the rack. The rockshaft L has, in addition to the lever arm or finger L', a lever arm or finger L3, which stands in a vertical fore-and-aft plane just outside of the rack N, and the dog Q has a lug or flange Q3, which overhangs the lever arm or finger L8 in position to be encountered IIO position. The two lever-arms L and L3, which y project from the rock-shaft L, are at such an angle to each other in view of the relative positionsoftheportionsorpoints of theleverKand dog Q, respectively, with which said leverarms respectively engage or against which they act, that when both said lever Kand dog Q are in the position for locking the rack B and rack-bar N, respectively, said lever and dog are in contact with the lever-arms L' and L3, respectively, so that the pressure of ,the two springs operating upon said lever and dog, respectively, checks the rock-shaft against rocking movement in either direction, causing it to be steady and free from rattling at lthe normal or locked position of both the parts which it controls, this normal position being intermediate the positions to which it is rocked in opposite directions to release, respectively, the dog which engages the circular rack and the dog which engages the rack-bar to permit the adjustment of the chair about its axis or the adjustment of the foot or leg rest and back with respect to the chair-bottom.

l. In combination with a chair-bottom, a base or support upon which it is vertically pivoted, a circular rack rigid with the base having its teeth inclined bodily in radial direction with respect to the plane of rotation, and a dog mounted on a chair-bottom guided in a direction parallel to the axis of rotation to engage between the inclined teeth of the rack.

2. In combination with a chair-bottom, a base or support upon which it is vertically pivoted, a circular rack rigid with such base having its teeth inclined with respect to a horizontal plane and beveled, anda dog mounted .on a chair-bottom guided vertically into engagexnent with the inclined and beveled teeth of the rack.

3. In combination with a chair-bottom, a

base or support upon which it is vertically pivoted, a circular rack rigid with such base, having its teeth inclined outwardly, and a dog guided on the chair-bottom adapted to be thrust vertically into engagement with the teeth of the rack, said dog being tapered in horizontal cross-section narrowed inwardly,

and a correspondingly-tapered seat in which it is guided; whereby the thrust of the dog into engagement with the inclined rack-teeth tends to crowd it into its tapered seat.

4. In combination with a chair-bottom, a base or support in which it is vertically pivoted, a circular horizontal rack rigid with such base having its teeth beveled and inclined with respect to a horizontal plane, a dog mounted on the chair-bottom and guided into and out of engagement with the rackteeth, said dog being tapered in horizontal cross-section and'provided with a correspondingly tapered seat whereby the pressure which tends to'hold it engaged with the rack, tends to wedge it into its tapered seat.

5. In combination with a chair-bottom, a standard to which it is secured, a foot or leg rest hinged to the chair-bottom, a rack-bar hinged to the foot or leg rest and extending under the chair-bottom alongside of the standard, the latter having a suitable lodgment for the rack-bar on which it may slide back and forward, a dog pivoted to the standard adapted to engage the rack, a rock-shaft jour vnaled on the chair-bottom and extending under the dog and provided with a lever-arm adapted to lift they dog as the shaft is rocked and a lever-arm extending up at the side of the chair for operating the rock-shaft.

6. In combination witha chair-bottom, a base or support upon which it is vertically pivoted, a circular rack rigid with the base and a dog mounted on the chair-bottom adapt ed to engage the rack, a foot or leg rest pivotally connected to the chair-bottom, a rackbar hinged to the foot or leg rest and extending under the chair-bottom, a dog mounted on the chair-bottom adapted to engage the rack-bar, a rock-shaft extending transversely under the chair-bottom having two leveri arms, one adapted to operate the dog which engages the circular rack, and the other adapted to operate the dog which engages the fore-and-aft rack-bar, said lever-arms and dogs and operating parts being so located respectively that the dogs are operated respectively by opposite rocking movements of the rock-shaft and means for rockingthe shaft in opposite directions at will.

In testimony whereof I have hereunto set my hand, at Chicago, Illinois, this 3d day of October, A. D. 1901.

ANTON N. HORNUNG, JR.

Witnesses:

OHAS. S. BURTON, GEORGE H. WARNER.

IOO

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